why dimenstion tables are denormalized in nature ?




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why dimenstion tables are denormalized in nature ? ..

Answer / siddu

For fast retrieval(to Perform a SELECT Operation)

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why dimenstion tables are denormalized in nature ? ..

Answer / vikki

GENERALLY IN DWH, WE DO SELECT QUERY ONLY(99%)..
SO THE DATA ARE NOT NEED TO BE NORMALIZED AS IN DB WHERE WE DO UPDATE,SELECT,ALTER,ETC..

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why dimenstion tables are denormalized in nature ? ..

Answer / ankit kansal

As a denormalized table structures for a database the number
of joins to fetch the data turns out to be less and hence selection to the data becomes faster.

selecting data from one table is always better than selecting the same data from multiple tables.


http://deepinopensource.blogspot.in/

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